#include <stdio.h>


void swap(int* p1,int* p2)
{
	int n = 0;
	n = *p1;    //n = a;
	*p1 = *p2;    //a = b;
	*p2 = n;    //b = n;

}

int add(int x,int y)
{
	int sum = 0;
	sum = x + y;

	return sum;

}


int main()
{
	int a = 10;
	int b = 20;
	swap(&a, &b);
	printf("a=%d,b=%d\n", a, b);
	
	printf("a+b=%d\n", add(a, b));
	return 0;
}